Find 1st Empty Cell In Row From A Column

I am trying to find code that will find the first empty cell in a row and add data in cell left to right. This code is filling all data in the last cell of the row and I am hoping to have it loop through data and fill the first empy cell (M1) and next data placed (m2) and so on

Sub Reportdates()
Dim Grid As Range, Gridcell
Dim Crit1 As Range
Dim Crit2 As Range
Set Grid = ThisWorkbook.Worksheets("sheet3").Range(" dates")
Set Crit1 = ThisWorkbook.Worksheets("Stageing").Range("J1")
Set Crit2 = ThisWorkbook.Worksheets("Stageing").Range("K1")
For Each Gridcell In Grid
If Gridcell.Value >= Crit1 And Gridcell.Value <= Crit2 Then
ThisWorkbook.Worksheets("Stageing").Range("M1").End(xlToRight).Offset(0, 0) = Gridcell.Value
End If
'Exit For
Next Gridcell
End Sub